Production of olefines and diolefines



Patented Mar. 7, 1933 UNITED STATES PATENT OFFICE OTTO 80mm, 0! LUDWIGSHAIEN-ON-THE-BHINE, MAX TBEPPENHAUER, 0]

Km AND OTTO GROSSKINSKY AND HEINRICH FISCHER, OF LUDWIGB- EAFEN-ON-THE-BHINE, GERMANY, ASSIGNORS TO I. G. FABBEN-INDUBTBIE AK- TIENGISELLSCEAIT, OI FRANKFORT-ON-THE-MAIN, GERMANY, A CORPORATION PRODUCTION OF OLEFINES AND DIOLEFINES Io Drawing. Application fled July 81, 1928, Serial 110. 294,566, and in Germany August 89, 10:11.

This invention relates to the manufacture and production of olefines and diolefines.

We have found that olefines and diolefines are obtained in a highly advantageous manner by bringing parafiins or olefines, or mixtures thereof containing at least six carbon atoms in the molecule, in particular those which are liquid at ordinary temperatures, which initial materials may also be cyclic and which are hereinafter referred to for the sake of brevity as non-aromatic hydrocarbons into contact in a va rous state and at an elevated temperature avorable for the reaction with a catalyst consistin of or containing a special form of carbon, t e surface of which has a high lustre and the roperties of which vary somewhat accordmg to the substratum on which it has been deposited and which is hereinafter referred. to for the sake of brevity as lustrous carbon. Preferably temperatures ranging between about 500 and 800 C. are employed and particularly good results have been obtained between 550 and 750 C.

The preparation of the said carbon having a high lustre is described, for example, in the Berichte der Deutschen Chemischen Gesellschaft, vol. 56, p. 2071 and vol. 59, p. 2433. It is advanta cons to employ the said lustrous carbon deposited, for example, on substrata, especially the diflicultly reducible metallic oxids which expression is also intended to include the com ounds and mixtures thereof. -The oxids o the alkali metals or their hydroxids, preferably on carriers, and salts, especially the alummates, chromates, tungstates, vanadates, uranates, phosphates, and also oxids of elements of the second group of the periodic system, such for example as oxids of magnesium, glucinum or salts of the alkaline-earth metals, for example, aluminates, or tertiary calcium phosphate and also the oxids of the elements scandium, titanium, yttrium, zirconium, tungsten, molybdenum, and uranium, and the like, or mixtures of the same, or their compounds are suitable for use as substrata for the lustrous carbon to be deposited. When operating in the presence of water va or we ave found that it is sometimes ina visable to employ such oxids or compounds or mixtures thereof as carriers for the lustrous carbon under the conditions of working as accelerate the production of water gas from carbon and water vapor, since in this case the lustrous carbon may be consumed in rather a short time. The difficultly reducible oxids of the elements, which are situated on or near the minima of the curve of atomic volume, such as aluminium, chromium and zinc are also suitable as substrata for the said lustrous carbon, especially for the production of butadiene hydrocarbons and they may further be employed in the form of their salts, such as phosphates, chromates, vanadates and the like. Thus for example good results are obtained with aluminates of metals forming diflicultly reducible oxids, such as calcium, zinc, and the like, and also with other compounds of the diflicultly reducible metallic oxids with each other, such as the vanadates, chromates and tungstates of calcium, zinc and aluminium.

The said 'substrata may be used either in the lump form, or may be deposited on carriers, for which urpose carriers composed for example of t e silicates of magnesium and aluminium are suitable. Metals may also be present in the contact masses, for example metals, such as copper, silver, molybdenum and tungsten, which have only a weak dehydrogenating action. When metals, such as iron, nickel and the like which have a powerful dehydrogenating action are used, they are beneficial only if added in small quantities, but harmful if added in large amounts, because in the latter case they efiect extensive decomposition of the hydrocarbons with the formation of carbon and hydrogen.

Also other substances, such as quartz, natural or artificial silicates, active silica or porcelain, or on metals such as copper, metallic chromium and the like may be employed as substrata. It has been found particularly advantageous to employ as carriers such substances as have a very low apparent specific gravity. The employment of catalysts containing the said varieties of lustrous carbon effects a particularly smooth formation of butadiene hydrocarbons.

Typical examples of cyclic paraffins and olefines which may be employed as initial materials according to the present invention are for instance cyclohexane, tetrahydrobenzene, tetrahydronaphthalene, terpenes and na hthenes, also for example Caucasian napht a, while as non-cyclic hydrocarbons may be mentioned for example, crude mineral oils, the conversion and cracking products thereof, the destructive hydrogenation products of carbonaceous substances, benzines and the like. Tars containing paraflins, such as brown coal tar, the tar obtained by low temperature carbonization and the like may also be employed as initial materials. Mixtures of non-cyclic paraflins and olefines with cyclic paraifins and olefines may also serve as initial materials.

The process may be carried out in the presence or absence of other gases and vapors acting as diluents, such for example as water vapor, nitro en, carbon dioxid, methane and the like. oreover, and this is a point of special importance, when water vapor which has proved particularly beneficial in the present process, is used as a diluent, the employment of lustrous carbon leads to the formation of reaction gases which contain no appreciable amounts of carbon dioxid or of carbon monoxid, so that under these circumstances, practically no losses of organic substances. are occasioned through combustion with the combined oxygen of the water, even when the reaction temperature rises to a very high level.

The process is preferably conducted at ordinary or reduced pressure, and preferably in the presence of diluents. Suitable diluents comprise all gases and vapors which have practically no action upon the substances taking part in the reaction at the temperatures employed. The employment of diluents and of reduced pressure are both considered to fall within the meaning of the term rarefaction hereinafter employed for the sake of brevity. The employment of water vapor, for example, is very suitable, since the diluent can be easily eliminated from the resulting reaction mixture. The further treatment of the reaction mixture obtained according to this process may consist, for example, in fractional distillation under pressure.

The following examples will further illustrate the nature of the said invention which however is not limited thereto.

Example 1 Cyclohexane vapor is passed at 650 centigrade, through a reaction vessel filled with porcelain balls, the porcelain thereby becommg coated with the above described lustrous carbon. There is then passed through the said reaction vessel a mlxture consisting of 4 parts by volume of water vapor and 1 part by volume of cyclohexane vapor, at a temperature exceeding 650 centigrade. After separating the water and the unaltered cyclohexane, a gaseous mixture, is obtained which contains 10 per cent by weight of hydrogen and methane, and 90 per cent by Weight of olefines, chiefly butadiene and ethylene. The reaction mixture is practically free from carbon oxids. The separation of the reaction products may be effected by fractional distillation under pressure. The yield of butadiene is from 60 to per cent of the theoretical. Similar results are obtained if in the above example copper granules are employed in the place of the porcelain balls.

E example 2 mixture is obtained consisting of about 90 per cent by weight of olefines, chiefly butadiene and ethylene. Only insignificant amounts of oxids of carbon can be detected. In place of cyclohexane, the homologues of that substance and also other monoand poly-nuclear cycloparafiins may be employed in a similar manner.

Example 3 The vapors of American petroleum mixed with about'an equal amount by weight of water vapor are passed at a temperature of 700 centigrade over a catalyst consisting of magnesium oxid coated with the said lustrous carbon. The mixture of olefines issuing from the reaction vessel is separated from methane and nitrogen by compression or by cooling to low temperatures after water and the liquid components have been condensed, whereupon the olefines are separated as for example by distillation under pressure. About 80 parts of olefines containing about 12 parts 0 butadiene are obtained from 100 parts of vaporized petroleum.

Example 4 The vapors of synthetic benzine, obtained by the destructive hydrogenation of brown coal, are mixed with about an equal amount by weight of water vapor and passed at 720 centigrade over silica gel, which has been coated with the said lustrous carbon. The mixture of olefines issuing from the reaction vessel, isseparated from methane and hydrogen by cooling to low temperatures or by 16 parts 0 compression, after water and the liquid components have been condensed. The olefines are separated by distillation under pressure. About 80 arts of olefines containing about butadiene are obtained from 100 parts of the vaporized benzine.

What we claim is 1. A process for the production of olefines and diolefines which comprises bringing a non-aromatic hydrocarbon containing at least 6 carbon atoms in the molecule in a vaporous state and at a temperature between about 500 and 800 G. into contact with lustrous carbon.

2. A process for the production of olefines and diolefines which comprises bringing a non-aromatic hydrocarbon containing at least 6 carbon atoms in the molecule in a vaporous and rarefied state and at a temperature between about 500 and 800 G. into contact with lustrous carbon.

3. A process for the production of olefine's and diolefines which comprises bringing a non-aromatic hydrocarbon containing at least 6 carbon atoms in the molecule in a vaporous state and at a temperature of between about 550 and 800 (.1. into contact with lustrous carbon;

4. A process for the production of olefines and diolefines which comprises bringing a liquid non-aromatic hydrocarbon in a vaporous and rarefied state and at a temperature of between about 550 and 800 G. into contact with lustrous carbon.

5. A process for the production of olefines and diolefines which comprises bringing a liquid non-aromatic hydrocarbon in a vaporous state and at a temperature between about 500 and 800 G. into contact with lustrous carbon deposited on carriers.

6. A process for the production of olefines and diolefines which comprises bringing a liquid non-aromatic hydrocarbon in a vaporous state and at a temperature between about 500 and 800 G. into contact with lustrous carbon deposited on a carrier consisting of a difiicultly reducible metal oxid.

7 A process for the production of olefines and diolefines which comprises bringing a liquid non-aromatic hydrocarbon in a vaporous and rarefied state and at a temperature between about 500 and 800 G. into contact with lustrous carbon deposited on a carrier consisting of a difiicultly reducible metal oxid.

8. A process for the production of olefines and diolefines which comprises bringing a non-aromatic hydrocarbon containing at least 6 carbon atoms in the molecule in a vaporous state and diluted with a vapor having practically no action upon the substances takmg part in the reaction and at the temperatures employed at a temperature between about 500 and 800 G. into contact with lustrous carbon.

9. A process for the production of olefines and diolefines which comprises bringing a non-aromatic hydrocarbon containing at least 6 carbon atoms in the molecule in a vaporous state and diluted with water vapor at a temperature between about 500 and 800 G. into contact with lustrous carbon.

10. A process for the production of olefines and diolefines which comprises bringing a liquid non-aromatic hydrocarbon in a vaporous state and diluted with water va or at a temperature of between about 700 an 800 centigrade into contact with lustrous carbon.

11. A process for the production of olefines and diolefines which comprises bringing a liquid non-aromatic hydrocarbon in a vaporous state and with diluted water va or at a temperature of between about 700 an 800 centigrade into contact with lustrous carbon deposited on carriers.

12. A process for the production of olefines and diolefines which comprises bringing cyclohexane in a vaporous and rarefied state and at a temperature between about 650 and 800 G. into contact with lustrous carbon.

13. A process for the production of olefines and diolefines which comprises bringing cyclohexane in a vaporous and rarefied state and at a temperature of between 7 00 and 800 G. into contact with lustrous carbon.

14. A process for the production of olefines and diolefines which comprises bringing cyclohexane in a vaporous state and diluted with water vapor at a temperature of between about 700 and 800 G. into contact with lustrous carbon.

15. A process for the production of olefines and diolefines which comprises bringing cyclohexane in a vaporous state and diluted with water vapor at a temperature of about 700 G. into contact with lustrous carbon deposited on magnesite.

16. A process for the production of olefines and diolefines, which comprises bringing a non-aromatic hydrocarbon containing at least 6 carbon atoms in the molecule in a vaporous state and at a temperature of between about 550 and 800 G. into contact with lustrous carbon deposited on a .substance selected from the group consistin of diflic'ultly reducible metallic oxides, t eir compounds and mixtures thereof.

17. A process for the production of olefines and diolefines, which comprises bringing a non-aromatic hydrocarbon containing at least 6 carbon atoms in the molecule in a vaporous state and at a temperature of between about 550 and 800 G. into contact with lustrous carbon deposited on magnesite.

18. A process for the production of olefines and diolefines, which comprises bringing a non-aromatic hydrocarbon containing at least 6 carbon atoms in the molecule in a vaporous-state and at a temperature of between about 550 and 800 G. into contact with lustrous carbon deposited on porcelain.

19. A process for the production of olefines and diolefines, which comprises bringing a non-aromatic hydrocarbon containing at least 6 carbon atoms in the molecule in a vaporous state and at a temperature of between about 550 and 800 G. into contact with lustrous carbon deposited on magnesium oxide.

20. A process for the production of olefines and diolefines, which comprises bringing cyclohexane in a vaporous state and at a temperature of between about 550 and 800 G. into contact with lustrous carbon deposited on a substance selected from the group consisting of the oxides and salts of alkali metals and alkaline earth metals.

21. A process for the production of olefines and diolefines, which comprises bringing cyclohexane in a vaporous state and at a temperature of between about 550 and 800 G. into contact with lustrous carbon deposited on an aluminate.

22. A process for the production of olefines and diolefines, which comprises bringing cyclohexane in a vaporous state and at a temperature of between about 550 and 800 G. into contact with lustrous carbon deposited on tertiary calcium phosphate.

In testimony whereof we have hereunto set our hands.

OTTO SCHMIDT.

MAX TREPPENHAUER. OTTO GROSSKINSKY. HEINRICH FISCHER. 

